Flue Through Roof Space

Flue design also has an impact on flue efficiency.

Flue through roof space.

Clay and concrete are alternative options. The vertical flue at the ceiling level is surrounded by and attached to a horizontal piece of open 1 2 x 1 2 metal mesh screen about 10 square. A single wall metal flue vent is not safe if it passes through combustible floors walls ceilings roofs. Vertical flues can pose issues due to the need to direct the duct through the roof space.

Bends or offsets in the flue can retard the steady outflow of gases. Often this is 50mm or 60mm but it does vary. The minimum clearance may be reduced by 50 percent to 225 mm 9 in if suitable shielding is installed either on the pipe or on the combustible surface. A flue pipe must never pass through a combustible floor or ceiling or through an attic roof space closet or concealed space.

That s because the combustion byproducts are in a gaseous form so the gases can float up through the flue pipe and out of your roof. The gas vent chimney for the furnace should extend at least 3 feet above the highest point where it passes through a roof and at least 2 feet higher than any portion of the house within a horizontal distance of 10 feet. Vertical flues the majority of boiler flues exit out of a wall horizontally but if the flue from your boiler comes out at roof level then there are also some regulations that need to be considered. 450 mm 18 in.

Position the vent pipe up to the bottom of the roof. If your boiler flue has to face out onto a public space the installer will have to ensure that it s fitted at least 2 1 metres above ground level over head height. When twin wall flue passes through a cupboard storage space or roof space a guard should be placed that is not closer than the distance to combustibles for that type of flue. Minimum clearance from combustible material.

If the roof isn t easily accessible or the engineer isn t worthy of an extras role in the bfg this means that scaffolding may be needed and that roof tiles will need to be moved or replaced. The metal furnace flue extends vertically through the closet ceiling through the attic and roof. With the pipe in a vertical position trace around the pipe using a pencil. Your twin wall flue should have a label with it which will show the distance to combustibles on it.

The penetration will be oval to have a round pipe exit vertically through a pitched roof you need an oval hole in the roof.